My sister had accommodations in college for a learning disability, and they usually put her in separate room. In cases when she didn't have a separate room, as she was one of the last to finish (with the others who also had extended time accommodation), people didn't notice at all.
She qualified for extra time to take the MCAT next month (that process is a whole other discussion). We're not sure how that is going to be handled at the testing center. PM me if need further information.